Currently, in applications such as machine-to-machine (M2M) communication or smartphone, services of small packets often need to be transmitted. For example, a daemon of a smartphone often initiates services of small packets whose data amount is generally less than 200 bytes. The services of small packets are characterized by small amounts of data and by being transmitted periodically or aperiodically.
Before initiating a service of small packets, a user equipment (UE) needs to perform random access. Because the services of small packets have a very small amount of data but lead to very large signaling overhead and delay in the random access process, the transmission efficiency of services of small packets is very low.